Splinter (2008)

A young couple retreats to the wilderness for a romantic camping weekend, but their idyll is shattered when they are car-jacked by an escaped convict and his girlfriend on the run from the police. As the foursome travel the back roads together, each plotting their next move, they find themselves in deeper trouble than any of them could have imagined--a blood-crazed, parasitic creature that absorbs the corpses of its victims has laid claim to the woods, and the two couples are now in its sights. Finding shelter at an abandoned gas station, they must use their wits and every weapon at their disposal to stave off the onslaught, not only from the insatiable creature, but also each other.